It is necessary for an existing vapor deposition apparatus to include a metal mask disposed between a backboard and a plasma generating source for masking due to a need of preventing from occurrence of a film forming phenomenon at an adhesive-coated zone of the backboard. This is generally realized by welding the metal mask to a stainless steel framework and then placing the stainless steel framework into the vapor deposition apparatus.
However, a metal mask generally made of a ferrum-nickel alloy will react with fluorine ions within a vacuum chamber, which affects a service life of the metal mask. Existing techniques have attempted to overcome the above-mentioned drawbacks by plating a coated layer that resists plasma onto a metal mask upon the metal mask being welded to the stainless steel framework. However, the stainless steel framework is liable to be deformed and then results in a shadow effect on the backboard; furthermore, metal frameworks in different sizes have to be used in cooperation with metal masks in different sizes. This makes the use of such kind of vapor deposition apparatus become cumbersome.